Burnt my arm

while checking the suction line to see if the unit was cooling. Surpirse!:shock:
Didn’t know the other one could fry an egg.


What a coincidence. I was posting the same question. Lennox heat pump. 8 years old. 42 degrees outside. VAV system. Both stats set 6 degrees above inside. Let it run 30 minutes. Suction line was 150 to 160 with a non-clamp sensor. I have seen em run 80 to 100 above ambient but holy smokes this one surprised me even after 25 years of inspecting. Need to brush up on HP. I do not see them often. Any comments on a 150 degree suction line?

When I was young I was always learning; now I am old and trying to remember what I forgot. :stuck_out_tongue:

It was 85 degrees here today and it was an a/c unit.
It was also the small line not the large suction line. :wink:

That line should have been about as warm as my hand today.

but to answer your question, 150 for a suction line is pretty warm but doesn’t seem unusual. I have grabbed my share that you don’t hold for long.

Well there ya go. I’m wearing a sweater; your in shorts and we both get burnt by an ac. :wink:

Its also the first heat pump I have seen that did not have aux heat option on the stat. A first for me.

that’s a pretty hot liquid line… was the fan stuck @ condenser or a tarp around it? Somethings afoul… head pressure through roof maybe.

Fan was running; coils clean. Temp in 2 story VAV was about equal. By pass damper in place. Perhaps I moved the thermostats up too fast. Home was 70 and I set them at 74. When home met demand I moved them up to 78. Air filter was an after market foam washable type that could have restricted air flow but it did not look dirty. I recommended HVAC service call but find I need to go back to class. :roll:

What was the type of refrigerant in the unt if it was R22 your temp may be a little warm what did the condenser fins look like

How fast you moved the stats up really has no effect on the system being you said no aux heat strips. If the compressor and reversing valve is in the heat mode it can only produce heat based on its refrigerant charge. If the indoor temp climbed from 70 to 74 in a reasonable amount of time to me you have no problem

R22. Coils have some hail damage but not that bad IMO.

I don’t see HP often. This would be first I saw that did not have aux heat.

Picture attached.

No aux heat is a problem based on the fact the unit goes into defrost simply by reversing the flow of refrigerant which in turn dumps 50 degree air into the home during the complete defrost cycle unless there is a aux unit to temper the air

Is there a chance you missed the emergency heat setting on the stat on some stats it is hard to see. The data plate you posted would have nothing to do with the aux heat strips as they are added seperate during the inatial set up

If indoubt about aux heat you can always open the front on the AHU and see if you have one of these in the pic

I hope you guys with the high temps realize you have problems there…

Those lines never get that hot if things are ok.

John, you need to get rid of that damn electro-static filter.
Restricted air flow at the indoor coil will raise refrigerant temp/pressures in the heat mode.

Mine was a good old 1978 carrier in a vacation condo unit. The last a long time because they hardly get used. They cram all the condensors under an overhang which doesn’t help.

I didn’t dive in too much, just said “Fail” and advised it be reviewed.